Characteristic accumulator for slide rule cursors



Dec. 18, 195] J. J. SMIDL 2,579,019

CHARACTERISTIC ACCUMULATOR FOR SLIDE RULE CURSORS Filed June 18, 1951 JOSEPH-.1 SM/DL INVENTOR.

Patented Dec. 18, 1951 CHARACTERISTIC ACCUMULATOR FOR SLIDE RULE CURSORS Joseph J. Smidl, Portland, Oreg.

Application June 18, 1951, Serial No. 232,161

6 Claims. 1

My present invention comprises an improvement upon my prior Patents No. Re. 23,127, dated June 21, 1949, and No. 2,490,240, dated December 6, 1949, the invention having to do with an improved mechanism for accumulating the characteristics in slide-rule operations.

The principal object of the present invention is to provide an improved characteristic accumulator which may be associated with various sizes or'types of slide-rule cursors without requiring modification of the slide rule or of the cursor.

A further object of the present invention is to provide means of the foregoing type which is compact and of small size so that it may form a slight extension of the normal slide-rule cursor.

A further object of the present invention is to provide an improved mechanism for accumulating totals.

The foregoing and other objects and advantages of the present invention may be more readily ascertained by inspection of the following specification taken in connection with the accompanying drawing wherein like numerals refer to like parts throughout; while the features of novelty will be more distinctly pointed out in the appended claims.

In the drawing:

Fig. 1 is a front view, on an enlarged scale, of apreferred form of the present invention;

Fig. 2 is a plan view of the present invention;

Fig. 3 is a view looking in the same direction as Fig. 2, with portions of the top of the housing removed;

Fig. 4 is a vertical section taken substantially along line 4-4 of Fig. 2; and

Fig. 5 is an end view with a portion of the apparatus broken away.

The invention comprises a housing, portions of which provide means forming an endless trackway, the trackway comprising an outer wall It! and an inner Wall II. The outer wall surrounds and is aflixed to the edge of a baseplate I2 having the shape of an elongated, flattened oval. The inner wall II is attached to the upper surface of an inner plate l3 which snugly fits within the outer wall I and is held against the upper surface of the baseplate I2 by a pair of screws I4. The inner wall I I is spaced inwardly from the edge of the plate I3 so that the trackway is provided between the walls Ill and II. A plurality of indicia-bearing plates I are slidably mounted in end-to-end relation within the trackway so formed by the walls I0 and II the ends of the plates being rounded so that the plates may move round the curves at the ends of the trackway while maintaining substantially the same distance between plates. The outer surface of each plate bears a characteristic numeral I6 and the inner surface of each plate is provided with a recess I7. The characteristic indicia are arranged on the plates in ascending or descending order from a central plate bearin the numeral zero. Preferably there are twenty-one such plates so that indicia may be accumulated in one direction from zero to plus ten and in the opposite direction from zero to minus ten. The trackway is enclosed by the outer edge of a cover plate I3 having a flange I9 affixed thereto, the flange snugly fitting around the upper edge of the outer trackway member ID. The inner wall II extends to a greater height than the outer wall ID and the plates I5 are of such height as to extend above the outer wall. The outer wall III and the flange I9 are provided with registerin notches which frame a window opening 20 through which the indicia may be seen one at a time as illustrated in Fig. l. The opening 20 is midway of one of the elongated sides of the trackway, and midway of the opposite side of the trackway there is provided a limiting lug 2i which projects above the upper edge of the outer wall III. The indicia plate I5 which carries the numeral zero is provided with an overhanging flange 22 which projects into the space between the upper edge of the wall I0 and the lower surface of the cover plate I8 so as to be engageable with the lug 2|, the lug 2| and the flange 22 providing cooperating limiting means on the wall and the plates, respectively, for limitin the extent of movement of the plates in any one direction. When the flange 22 engages lug 2| in one direction the plate bearing the numeral plus ten will be visible in the window 28, and in the other direction the plate bearing the numeral minus ten will be visible in the window 20.

A reciprocable member comprising a troughshaped member 25 is slida-bly mounted within the housing. the base of member 25 resting upon the inner plate I 3, and its upwardly extendin flanges being slidably guided by the elongated straight portions of the inner wall II. A threaded post 26 extends upwardly from the center of the member 25 through an elongated slot 21 in the cover plate I8 and through a central opening in a limiting plate 28 slidably mounted upon the upper surface of the cover plate I8, the assembly eing held together by a nut 29 projecting above the surface of the limiting plate 28. The reciprocable member 25 is normally maintained in a central, neutral position by a pair of opposed springs 30 tensioned between the opposite edges of the member and anchoring members associated with the screws M. The upper edge of the flange l9 projects above the plate IE to provide guides for plate 28 and limiting means to arrest the movement of plate 28 in either direction. A pair of cross rods 31 extend between the vertical flanges of the reciprocable member 25, one on each side of the threaded post 26, and provide means for pivotally mountin a pair of dogs 32, the forward ends of which project through elongated slots 33 in the wall I l and are urged to project through the slots by a spring 34 having its intermediate portion coiled about the post 26. The dogs are thus normally urged through the slots 33 into engagement with the rear surfaces of the plates Hi, the tips thereof normally resting within the confines of a pair of the grooves I! in the back surfaces of the plates.

,When it is. desired to accumulate characteristic indicia the nut 29 is engagedby a finger and moved in the desired direction, thus causing one of the dogs 32, the one which points in the direction of movement, to engage the edge of one of the grooves l! and displace the entire line of plates to the extent permitted by the flange l9 engaging the end of the plate 28. During this movement the trailing dog is retracted upon engagement with the end of its slot 33. When the nut 29 is released the tension spring returns the sliding member to its neutral position, thereby causing both dogs to return to a position of readiness for actuation in either direction, the dogs locking the plates in position. Each actuation of the nut 29 from its neutral position to its limit position causes displacement of the line of plates by the width of one of the plates, thereby causing the indicia to appear in the window one at a time. The operator will, of course, displace the nut 29 in one direction for positive characteristics and in the opposite direction for negative characteristics, the final characteristic of a series of operations being the final numeral to appear in the window 20.

A -form of mounting means whereby the accumulator may be associated with a standard form of slide-rule cursor is illustrated, the same comprising a pair of opposed clamps. Each clamp comprises a depending stirrup 35 in which is mounted the sliding stem 36 of a clamp 31, the jaw thereof having side plates for engagement with the upper and lower surfaces of the top bar of a slide-rule cursor indicated at 38 in Fig. 1, and a hook 39 for engagement beneath the end of the top bar. A screw 40 is preferably mounted in the stirrup 35 for retaining the stem 36 in adjusted position. Any other suitable form of means for mounting the accumulator on a sliderule cursor may be provided in lieu of the illustrated form.

Having illustrated and described a preferred embodiment of the present invention, it is to be appreciated that the same permits of modification in arrangement and detail. All such modifications; as come within the true spirit and scope of the appended claims are considered to be a part of my invention.

I claim;

1. A characteristic accumulator for use in connection with a slide rule, comprising means forming a trackway, a plurality of indicia-bearing plates mounted end to end in said trackway and guided thereby for sliding movement therealong, a sliding member mounted for reciprocable movement alongside of said trackway forming means, means limiting the movement of said sliding member in either direction, resilient means normaly' maintaining said sliding member in a neutral position, a pair of oppositely directed, spring-urged dogs mounted upon said sliding member and both normally projecting into said trackway and into engagement with said plates, and means associated with said trackway forming means to retract the trailing one of said dogs while the forward one of said dogs is in engagement with said plates when said sliding member is moved in either direction from said neutral position, the extent of movement of said sliding member in either direction being such asto cause the plate-engaging dog to displace said plates by the width of one of said plates, said trackway forming means having a window therein through which the indicia of one of said plates may be viewed.

21A characteristic accumulator for use in connection with a slide rule, comprising means forming a trackway, a plurality of indicia-bearing plates mounted end to end in said trackway and guided thereby for sliding movement therealong, a sliding member mounted for reciprocable movement alongside of said trackway forming means, means limiting the movement of said sliding member in either direction, resilient means normally maintaining said sliding member in a neutral position, a pair of oppositely directed, spring-urged dogs mounted upon said sliding member and both normally projecting into said trackway and into engagement with saidplates, means associated with said trackway forming means to retract the trailing one of said dogs while the forward one of said dogs is in engagement with said plates when said sliding member is moved in either direction from said neutral position, the extent of movement of said sliding member in either direction being such as to cause the plate-engaging dog to displace said plates by the width of one of said plates, said.

trackway forming, means having a window therein through which the indicia of one of said plates may be viewed, and cooperative means associated with one of said plates and with said trackway for limiting the accumulated movement of said plates in either direction.

3. A characteristic accumulator for use in connection with a slide rule, comprising means providing an endless trackway, a plurality of.

characteristic-bearing plates mounted end to end in said traokway and capable of sliding said dogs is in engagement with said plates when said sliding member is moved in either direction from said neutral position, the extent of movement of said sliding member in either direction being such as to displace said plates by the width of. one of said plates, said trackway having a window therein through which the indicia of one of said plates may be viewed. I

4. A characteristic accumulator for use in connection with a slide rule, comprising means providing an endless trackway, a plurality of characteristic-bearing plates mounted end to end in said traekway and capable of sliding movement thereabout, a sliding member capable of reciprocation within the orbit of said trackway, means limiting the extent of movement of said sliding member in either direction, resilient means normally maintaining said sliding memher in a neutral position from which it may move an equal amount in either direction, a pair of opposed, spring-urged dogs mounted upon said sliding member and both normally projecting into said trackway and into engagement with said plates, means associated with said trackway forming means to retract the trailing one of said dogs while the forward one of said dogs is in engagement with said plates when said sliding member is moved in either direction from said neutral position, the extent of movement of said sliding member in either direction being such as to displace said plates by the width of one of said plates, said trackway having a window therein through which the indicia of one of said plates may be viewed, and means associated with one of said plates and with said trackway for limiting the accumulated movement or said plates in either direction.

5. In a characteristic accumulator for association with a slide-rule cursor, means providing an endless trackway, a plurality of substantially rectangular plates mounted end to end in said trackway and each bearing a charactistic numeral on its outer surface, said trackway having a window provided in the outer surface thereof through which one of said characteristic numerals may be viewed, said plates having characteristic numerals thereon in ascending and descending order from zero, sliding means associated with said trackway forming means and comprising a pair of oppositely acting dogs for moving said plates the width of one of said plates at each operation thereof, means for reciprocating said sliding means, means to limit the movement of said sliding means, and resilient means to return said sliding means to an intermediate position after each actuation thereof.

6. In a characteristic accumulator for association with a slide-rule cursor, means providing a trackway, a plurality of substantially rectangular plates mounted end to end in said trackway and each bearing a characteristic indicia on its outer surface, said trackway having a window provided in the outer surface thereof through which one of said characteristic indicia may be viewed, said plates having indicia thereon in ascending and descending order from zero, reciprocable means associated with said trackway forming means for moving said plates the width of one of said plates at each operation thereof, means for limiting the movement of said reciprocable means, and resilient means to return said reciprocable means to an intermediate position after each actuation thereof.

JOSEPH J. SMIDL.

No references cited. 

